What have you tried to do to fix this before asking? Have you checked the volume is not set to zero, have you checked your HDMI cable? Have you checked the sound on you TV? Have you checked another source to see if that works? Without tell people what your using what you've done how do you expect people to help?
Sorry Shiv but you ask such vague questions, no details or anything then post "Anyone?" as though members are supposed to know your full setup and what you have tried....... come on mate help yourself by helping us with details